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A372084
Number of acyclic orientations of the Turán graph T(n^2,n).
3
1, 1, 14, 122190, 4154515368024, 1835278052687560517522520, 26375779571296696625528695444035039796080, 25932533306693349690666903275634586837883421559437937952074800, 3259525010466811026507391843042719132975543560928683870154345751824625274129141118944640
OFFSET
0,3
COMMENTS
The Turán graph T(n^2,n) is the complete n-partite graph K_{n,...,n}.
An acyclic orientation is an assignment of a direction to each edge such that no cycle in the graph is consistently oriented. Stanley showed that the number of acyclic orientations of a graph G is equal to the absolute value of the chromatic polynomial X_G(q) evaluated at q=-1.
LINKS
Richard P. Stanley, Acyclic Orientations of Graphs, Discrete Mathematics, 5 (1973), pages 171-178.
Wikipedia, Multipartite graph.
Wikipedia, Turán graph.
FORMULA
a(n) = A267383(n^2,n).
a(n) ~ sqrt(2*Pi) * n^(2*n^2 + 1) / exp(n^2 + n/2 - 7/24). - Vaclav Kotesovec, Feb 06 2026
CROSSREFS
Main diagonal of A372326.
Cf. A267383.
Sequence in context: A013754 A073940 A164322 * A159430 A395234 A013800
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Apr 17 2024
STATUS
approved